The Effects of Shear Stress on Endothelial Cell Retention and Function on Expanded Polytetrafluoroethylene

Abstract

We evaluated the adherence of indium 111-radiolabeled endothelial cells to fibronectin-treated expanded polytetrafluoroethylene surfaces exposed to high (437 s-1) vs low (218 s-1) shear and the influence of shear on prostacyclin production. Canine jugular vein factor VIII-positive endothelial cells in passages 3 through 6 were incubated with 111Indium-oxine, and labeled cells were seeded onto fibronectin-treated expanded polytetrafluoroethylene patches. Patches with confluent cells were exposed to shear in a Weissenberg rheogoniometer for intervals ranging up to 60 minutes. Percent endothelial cell retention was determined by gamma counting of patches and media and by histologic evaluation. Prostacyclin production (tritiated radioimmunoassay of 6-keto-prostaglandin F1 alpha) was assayed on perfusing media. Results showed no differences in 6-keto-prostaglandin F1 alpha production between shear rates or time periods. Endothelial cell retention did not differ between the shear rates. Rotational shear caused persistent cell loss over time in either high- or low-shear conditions. This persistent cell loss in response to steady rotational shear differs from that in response to identical rates of pulsatile linear shear in our laboratory where cell loss approached zero after 15 minutes.

Iloprost in Alginate Decreases the Thrombogenicity of Expanded Polytetrafluoroethylene

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Tissue-Engineered Heart Valves: A Call for Mechanistic Studies

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Extraction of material parameters from a multilayer multi-harmonic thickness shear mode (MTSM) sensor data using genetic algorithm

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“…Cellular adhesion plays important roles in the regulation of cell behavior, such as the control of growth and differentiation during development and the modulation of cell migration in wound healing, metastasis, and angiogenesis. Biological interfacial processes have also a critical importance in determining clinical efficacy of bloodcontacting materials [2]. Deep understanding of these complex interactions and biological processes occurring at the interface will enable researches to develop novel bloodcompatible biomaterials.…”